Teen Drinking Tied to Bad Choices as Adult

Sept. 21, 2009 -- Abuse alcohol when you're young and you'll make unwise decisions later on in life, a new study suggests.

It is well known that too much alcohol can slow down a person's ability to think, react, and make decisions at the current moment. But scientists from the University of Washington in Seattle say teenage drinking may actually lead to bad decision making as an adult.

Previous studies have shown that drinking too much alcohol during adolescence can interrupt critical brain development. Ilene Bernstein and colleagues say their new experiment with rats shows that excessive alcohol use actually "rewires" the brain to choose unwisely in the future.

The team provided young, adolescent rats access to gelatin mixed with alcohol for 20 days. The rats gobbled down the alcoholic gelatin. Another group was provided nonalcoholic gelatin treats for the same amount of time.

Three weeks later, when the rats were considered adults, they were given two choices: Push a lever that always spits out two sugary treats, or push another one that may give them four yummy pellets -- or none at all.

The rats that essentially got drunk during adolescence were much more likely to push the lever that dispensed an uncertain number of treats -- a risky choice. The other, non-alcohol rats, more consistently chose the lever that would give them consistent rewards, in this case, two treats every time. The animals' decisions appeared similar three months later, well into what's considered rat adulthood.

Study researchers say their findings may help reveal a neurobiological link between teenage alcohol abuse and bad decision making in adulthood.

"Scientists believe regions of the brain, including those implicated in decision making, are slow to develop and development extends into adolescence. This study shows that these late-developing structures in rats are affected by high alcohol use," Bernstein says in a news release. "This research raises a concern that if the brain is permanently changed by alcohol we need to place more emphasis on preventing adolescent alcohol use."

The study appears in this week's online edition of the Proceedings of the National Academy of Sciences. The National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism funded the experiment.